Prognostic Factors for High Intraoperative Blood Loss for Multiple Myeloma-Related Bone Disease in the Spine

Study DesignRetrospective multicenter cohort study.ObjectivesSpine surgery for multiple myeloma (MM) is associated with an increased intraoperative blood loss. Therefore, this study aims to examine prognostic factors for higher intraoperative blood loss in spine surgery for patients with MM.MethodsIn total, 158 adult patients with MM undergoing spine surgery between May 2001 and December 2021 were included. The main outcome for intraoperative blood loss was the Bleeding Index (BI), next to the visually estimated blood loss (EBL). Two separate multivariable generalized linear models (GLMs) were utilized to assess the associations between the predictors and these two outcomes.ResultsThe average BI was 4.4 and average EBL was 750 mL. Compared to corpectomy with stabilization, other types of surgery (decompression with stabilization, sole decompression, sole stabilization) were associated with a lower expected BI, ranging from a 26.5% to 39% decrease. A cervical location of surgery was associated with a 40.3% reduction of expected BI compared to a lumbar location (<i>P</i> = 0.006). Lower platelet count (<i>P</i> = 0.003) and longer duration of surgery (<i>P</i> < 0.001) were associated with a higher expected BI. For EBL, ECOG score, surgery type, and duration of surgery were found as independent predictors.ConclusionsThis study identified lower platelet count, type of surgery, location of operated spinal levels, and a longer duration of surgery as independent predictors of higher intraoperative BI in MBD-related spine surgery. These outcomes can be relevant for preoperative screening, shared decision making, and perioperative blood transfusion deliberation or planning.